To be honest, Halo 1 was a poor game IMHO (single player, I don't know about multi). Tedious checkpoints (while most FPS at the time had save anywhere capability), lots of assets reuse (play half the levels, then the remaining half you backtrack on the same levels, nice trick guys...), bland environment (walls, floor, ceiling, not much else).

On a somewhat related note: there's a fan project to essentially bring Halo 3 multiplayer to PC (and Mac!). They even got official approval from 343 Industries. (I have to note, though, that their web design is a blatant rip-off of Bungie's.)

"We do what we must, because we can."
"Gaming on a Mac is like women on the internet." — "Highly common and totally awesome?"